Merge "libsnapshot: Fix test failures on certain configurations."

fs_mgr/libsnapshot/snapshot.cpp

@@ -3216,6 +3216,8 @@ Return SnapshotManager::CreateUpdateSnapshots(const DeltaArchiveManifest& manife
         vabc_disable_reason = "recovery";
     } else if (!cow_format_support) {
         vabc_disable_reason = "cow format not supported";
+    } else if (!KernelSupportsCompressedSnapshots()) {
+        vabc_disable_reason = "kernel missing userspace block device support";
     }
 
     if (!vabc_disable_reason.empty()) {

fs_mgr/libsnapshot/snapshot_test.cpp

@@ -124,6 +124,10 @@ class SnapshotTest : public ::testing::Test {
         SKIP_IF_NON_VIRTUAL_AB();
 
         SetupProperties();
+        if (!DeviceSupportsMode()) {
+            GTEST_SKIP() << "Mode not supported on this device";
+        }
+
         InitializeState();
         CleanupTestArtifacts();
         FormatFakeSuper();
@@ -159,7 +163,13 @@ class SnapshotTest : public ::testing::Test {
         IPropertyFetcher::OverrideForTesting(std::move(fetcher));
 
         if (GetLegacyCompressionEnabledProperty() || CanUseUserspaceSnapshots()) {
-            snapuserd_required_ = true;
+            // If we're asked to test the device's actual configuration, then it
+            // may be misconfigured, so check for kernel support as libsnapshot does.
+            if (FLAGS_force_mode.empty()) {
+                snapuserd_required_ = KernelSupportsCompressedSnapshots();
+            } else {
+                snapuserd_required_ = true;
+            }
         }
     }
 
@@ -176,6 +186,16 @@ class SnapshotTest : public ::testing::Test {
         LOG(INFO) << "Teardown complete for test: " << test_name_;
     }
 
+    bool DeviceSupportsMode() {
+        if (FLAGS_force_mode.empty()) {
+            return true;
+        }
+        if (snapuserd_required_ && !KernelSupportsCompressedSnapshots()) {
+            return false;
+        }
+        return true;
+    }
+
     void InitializeState() {
         ASSERT_TRUE(sm->EnsureImageManager());
         image_manager_ = sm->image_manager();
@@ -193,6 +213,11 @@ class SnapshotTest : public ::testing::Test {
         // get an accurate list to remove.
         lock_ = nullptr;
 
+        // If there is no image manager, the test was skipped.
+        if (!image_manager_) {
+            return;
+        }
+
         std::vector<std::string> snapshots = {"test-snapshot", "test_partition_a",
                                               "test_partition_b"};
         for (const auto& snapshot : snapshots) {
@@ -946,6 +971,11 @@ class SnapshotUpdateTest : public SnapshotTest {
         SKIP_IF_NON_VIRTUAL_AB();
 
         SnapshotTest::SetUp();
+        if (!image_manager_) {
+            // Test was skipped.
+            return;
+        }
+
         Cleanup();
 
         // Cleanup() changes slot suffix, so initialize it again.
@@ -2680,6 +2710,9 @@ class ImageManagerTest : public SnapshotTest {
         CleanUp();
     }
     void CleanUp() {
+        if (!image_manager_) {
+            return;
+        }
         EXPECT_TRUE(!image_manager_->BackingImageExists(kImageName) ||
                     image_manager_->DeleteBackingImage(kImageName));
     }

fs_mgr/libsnapshot/utility.cpp

@@ -29,6 +29,7 @@
 #include <fs_mgr/roots.h>
 #include <liblp/property_fetcher.h>
 
+using android::dm::DeviceMapper;
 using android::dm::kSectorSize;
 using android::fiemap::FiemapStatus;
 using android::fs_mgr::EnsurePathMounted;
@@ -251,7 +252,10 @@ bool CanUseUserspaceSnapshots() {
         LOG(INFO) << "Userspace snapshots disabled for testing";
         return false;
     }
-
+    if (!KernelSupportsCompressedSnapshots()) {
+        LOG(ERROR) << "Userspace snapshots requested, but no kernel support is available.";
+        return false;
+    }
     return true;
 }
 
@@ -278,5 +282,10 @@ bool IsDmSnapshotTestingEnabled() {
     return fetcher->GetBoolProperty("snapuserd.test.dm.snapshots", false);
 }
 
+bool KernelSupportsCompressedSnapshots() {
+    auto& dm = DeviceMapper::Instance();
+    return dm.GetTargetByName("user", nullptr);
+}
+
 }  // namespace snapshot
 }  // namespace android

fs_mgr/libsnapshot/utility.h

@@ -127,6 +127,8 @@ std::ostream& operator<<(std::ostream& os, const Now&);
 void AppendExtent(google::protobuf::RepeatedPtrField<chromeos_update_engine::Extent>* extents,
                   uint64_t start_block, uint64_t num_blocks);
 
+bool KernelSupportsCompressedSnapshots();
+
 bool GetLegacyCompressionEnabledProperty();
 bool GetUserspaceSnapshotsEnabledProperty();
 bool GetIouringEnabledProperty();